New Ag(I) and Pd(II) complexes derived from symmetrical and asymmetrical NHC precursors: Synthesis, Characterization, Antibacterial activity, and Theoretical calculations

New symmetric and asymmetric imidazolium salts namely 1-methyl-3-(2,5-dimethylphenyl)-acetamideimidazolium chloride (2), 1-benzyl-3-(2,5-dimethylphenyl)-acetamideimidazolium chloride (3) and 1,3-bis-(2,5-dimethylphenyl)-acetamideimidazolium chloride (4) were synthesized. In situ deprotonation technique was employed to synthesize Ag(I)-NHC complexes (5-7) from the reaction of Ag2O with the abovementioned ligand precursors. Subsequent reactions of Ag(I)-NHC complexes with [PdCl2(MeCN)(2)] resulted the Pd(II)-NHC complexes (8-10) via transmetallation method. All the synthesized compounds were characterized using various techniques such as H-1 and C-13 NMR, FTIR and CHN analysis. The antibacterial activity of all the compounds was evaluated against bacterial strains E. coli as gram-negative and S. aureus as gram-positive bacteria using azithromycin as a standard antibiotic. The density functional theory (DFT) method was used to optimize the structures of the synthesized compounds using Gaussian 09 and Molecular Graphic Laboratory (MGL). Electronic energy, HOMO, LUMO, and dipole moment were calculated as well. Further, the estimated anticancer activity of the compounds was determined using docking calculations. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

New symmetric and asymmetric imidazolium salts were synthesized and characterized using various techniques, with their antibacterial and anticancer activities evaluated.